My son caught this sunfish and I wonder what is going on. I suspect this might be a hybrid but of what? I have bluegill, redear sunfish and several years ago bought a bag of 100 what were called coppernose bluegill and the next year some of my bluegill looked different but nothing like this. One thing that is different is the feed I am using; I got a bag of koi food that the bag says helps produce better color. I fed it through most of the winter and we have been noticing that all of our fish have brighter colors but most of them look like normal fish but their colors are brighter and the orange/yellow breast color sometimes goes back to the tail.

Might be a Redear x Bluegill hybrid, male RES definitely darken up like that during the spawn but yours is lacking the red eartab characteristic of a pure RES. It does have a long pectoral fin and larger mouth which is a characteristic of RES.